Noun
A messenger between two parties.
A representative, or charge d'affaires, of the pope at a foreign court or seat of government, ranking next below a nuncio.
Source: Webster's dictionaryFormerly, the title (Apostolic) Internuncio denoted a papal diplomatic representative of the second class, corresponding to Envoy Extraordinary and Minister Plenipotentiary as a title for diplomatic representatives of states (cf. Source: Internet
Before 1829, Internuncio was the title applied instead to the ad interim head of a mission when one Nuncio had left office and his replacement had not yet assumed it. Source: Internet